Word: nebula
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...first inkling that pulsars might not be reliable timepieces came after Cornell University astronomers at Arecibo, Puerto Rico, trained their 1,000-ft. radio telescope on a newly discovered pulsar in the Crab Nebula, the glowing remnant of a supernova-or stellar explosion-that was seen from earth in A.D. 1054. Unlike most other pulsars, which have relatively low repetition rates (between one and four per second), the new find was ticking about 30 times per second. Carefully measuring the pulse rate in October and then again in November, the astronomers found that it was slowing down by about...
That is exactly why many artists find the concept so irresistible. Dennis Oppenheim displays a photograph of a giant nebula made out of aluminum chips that he sprinkled on a field out side New Haven, Conn. Michael Heizer shows a photograph of five holes he dug in the Black Rock desert in Nevada. Robert Smithson exhibits his Non-Site, five trapezoidal woodbins filled with chunks of ore, plus an aerial photograph of the mines in Franklin, N.J., whence they came. This is meant to allow the viewer to contemplate the fact that "140 minerals" are found in the earth...
...expected to contemplate each work for at least 30 minutes-which is what Irwin does. As time passes, lights and blushes interweave; the shadows on the wall seem to march up and join the painting, until the spectator may well feel as though he were gazing into a galactic nebula or a darkened...
Contracting Cloud. Though R Mon is a near neighbor, only 2,000 light-years away, its characteristics have universal implications. Most astronomers agree that the sun formed from a slowly rotating nebula-a cloud of dust and gas that gradually contracted because of gravitation, and began to rotate faster. When pressures at the dense center of the shrinking cloud produced enough heat, thermonuclear reactions took place and the sun began to burn, still surrounded by the outlying portions of the cloud-apparently the current state of R Man's evolution. As more of the particles fell toward the burning...
...sources outside the solar system. Their search was not rewarded until 1962, when more sensitive instruments picked up the first X-ray emissions from outside the solar system. But until this year, only one additional visible object had been definitely identified as an X-ray producer: the familiar Crab Nebula.* Though their relatively crude instruments sensed X rays from about two dozen other vaguely defined areas of the sky, astronomers have been un able to tell which, if any, of the known celestial bodies were producing them. Now X-ray astronomy seems to be coming of age. The strongest...